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+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/*
+ * This file is part of the LibreOffice project.
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ *
+ * This file incorporates work covered by the following license notice:
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed
+ * with this work for additional information regarding copyright
+ * ownership. The ASF licenses this file to you under the Apache
+ * License, Version 2.0 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.apache.org/licenses/LICENSE-2.0 .
+ */
+
+#ifndef INCLUDED_BASEBMP_STRIDEDARRAYITERATOR_HXX
+#define INCLUDED_BASEBMP_STRIDEDARRAYITERATOR_HXX
+
+#include <basebmp/metafunctions.hxx>
+
+namespace basebmp
+{
+
+/** Like vigra::StridedArrayIterator
+
+ Changed semantics re. DirectionSelector<StridedArrayTag>: stride
+ now counts in <em>raw</em> bytes
+
+ Adapts given ptr, in a way that iterator increments move forward
+ in strided steps. Stride can, by the way, also be negative
+ */
+template< typename T > class StridedArrayIterator
+{
+public:
+ typedef typename clone_const<T, unsigned char>::type internal_type;
+
+ /** Create iterator
+
+ @param stride
+
+ Stride in bytes. Given value should better match memory layout
+ of T, as memory gets reinterpret-casted.
+ */
+ explicit StridedArrayIterator(int stride, T* ptr = 0) :
+ stride_(stride),
+ current_(reinterpret_cast<internal_type*>(ptr))
+ {}
+
+ /** Copy from other StridedArrayIterator, plus given offset
+
+ @param offset
+ Offset in bytes
+ */
+ StridedArrayIterator( StridedArrayIterator const& rSrc,
+ int offset ) :
+ stride_(rSrc.stride_),
+ current_(reinterpret_cast<internal_type*>(
+ reinterpret_cast<T*>(rSrc.current_)+offset))
+ {}
+
+ void operator++() {current_ += stride_; }
+ void operator++(int) {current_ += stride_; }
+ void operator--() {current_ -= stride_; }
+ void operator--(int) {current_ -= stride_; }
+ void operator+=(int dy) {current_ += dy*stride_; }
+ void operator-=(int dy) {current_ -= dy*stride_; }
+
+ int operator-(StridedArrayIterator const & rhs) const
+ { return (current_ - rhs.current_) / stride_; }
+
+ bool operator==(StridedArrayIterator const & rhs) const
+ { return current_ == rhs.current_; }
+
+ bool operator!=(StridedArrayIterator const & rhs) const
+ { return current_ != rhs.current_; }
+
+ bool operator<(StridedArrayIterator const & rhs) const
+ { return *this - rhs < 0; }
+
+ bool operator<=(StridedArrayIterator const & rhs) const
+ { return *this - rhs <= 0; }
+
+ bool operator>(StridedArrayIterator const & rhs) const
+ { return *this - rhs > 0; }
+
+ bool operator>=(StridedArrayIterator const & rhs) const
+ { return *this - rhs >= 0; }
+
+ T* operator()() const
+ { return reinterpret_cast<T*>(current_); }
+
+ T* operator()(int d) const
+ { return reinterpret_cast<T*>(current_ + d*stride_); }
+
+private:
+ int stride_;
+ internal_type* current_;
+};
+
+} // namespace basebmp
+
+#endif /* INCLUDED_BASEBMP_STRIDEDARRAYITERATOR_HXX */
+
+/* vim:set shiftwidth=4 softtabstop=4 expandtab: */